Anyone own a 7mm 300 Win Mag?

[RockZ]

Broz,
I read all of your past posts and worked up from low powder charges and ran many simulations on quick load with the rws brass capacity and all I could get was 3050fps. I start with loads in the 50kpsi pressure range. I wasn't surprised at pressure at low charges I was surprised by the low max velocity with that specific combination. I simply just got much less velocity than with win and Norma brass.
I tried h1000 with win brass but not Norma. It worked out ok but not as good as retumbo.
I went with retumbo because I could take best advantage of the case capacity and still keep pressures lower with good velocity. Plus on quick load z1 and pmax lined up well as far as I can remember.

 

[Broz]

I went with retumbo because I could take best advantage of the case capaacity

Ok Thanks, but doesn't it take more Retumbo than H-1000? I was looking for a little more case capacity and that's why I didn't like the RWS.

Jeff

 

[RockZ]

Broz,
No , it doesn't take more retumbo on a volume basis but it allows a larger more sufficient charge of retumbo (that smaller capacity cases won't allow). This enables us to take advantage of and get the best results considering volume fill percentage,burn rate and pressure curve characteristics.
With h1000 you hit pressure way before case volume limitations ,but you can fit quite a bit more h1000in the case than retumbo.

 

[RockZ]

Broz ,
I read your question again. If you are asking am I using a higher powder charge with retumbo than h1000.
The answer is yes.

 

[chuckhammer]

Anyone tried Reloader 33 in this or similar cartridges? Likely more temperature sensitive that the Hodgdon "extreme" powders like H1000 and Retumbo but appears to yield a bit more zip for the same pressure. Going off of QL, that is.

 

[Broz]

Broz ,
I read your question again. If you are asking am I using a higher powder charge with retumbo than h1000.
The answer is yes.

Yeah, that's what I was saying. or trying to

 

[smack]

What size bushing are you guys using for the winchester unturned .300 Win mag brass for sizing. I have a 7mm-300 Variant called a 7.21 Sage it is almost identical to the Valkeri print in this thread with the acceptation of a 35 degree shoulder. I had mine done last year, reamer that is. I'm just getting a barrel chambered now.

 

[garou22]

My Unturned Bushing Size For The Redding Dies Is .313, Turned Size Is .311. Brass Is Norma, Primer Is CCI 250, Bullet Is Berger 180 VLD hunter .284, Powder Is H4831 @ 76Gr., Seat Depth Is .130, Muzzle Velocity Is 3056fps Avg. @ 84 Deg F 30.15InHg 3450Ft (29.92InHg @ 3670 Ft), SD Of 09, Avg 5 Shot 300 Yard Group Is 1.1 Inches With An At Range Velocity Of 2750Fps (Same Atmospheric DataAsMuzzle), Corrected B.C. Is .348 G7.

 

[Skyking]

Had a great day shooting yesterday. Some of the best 100 yard group that I have shot with this gun.



http://s747.photobucket.com/user/cr_jeeper/media/7-300/300_zpse296c12b.jpg.html

 

[smack]

Great groups! Can't wait to get mine chambered up.

 

[chuckhammer]

Nice groups, Skyking.

 

[Dick Tinsley]

Really great groups, Skyking!!! What velocity with that load?

 

[Buck300]

Ha Ha!! The exceptional rifle that shoots this good is hard to come by for sure. But then, exceptional friends are even harder to come by. Remember now, I agreed to sell him this rifle before I was done testing it. I have to shoot a rifle many times in many different situations before they steal my heart. By then the deal was already done and I simply kept my word just like you guys would do.

Plus, I had my new full custom 300 win in the works. I don't need a 7mm-300 and a 300 win. If the 300 win does not shoot as good as this rifle I could always rebarrel it to 7mm-300... See, I do have a back up plan...

LOL, this reminds me of the movie....? either "Wyatt Earp" or "Tomb Stone" ?? Where the guy asked Doc Holiday

" why are you doing this you will be killed"

Doc, " Cuz Wyatt is my friend"

guy " Hell, I have lots of friends"

Doc " Well I don't "

Ha ha!!!


Jeff

The 7mm Practical is very similar to this cartridge, take a look on terminal ballistics research. Im interested

 

[AZShooter]

Nice groups Skyking!

Chuckhammer: I have a 7mm/375 Ruger not the LRM. It is a 375 Ruger case necked down short neck and all.

Using RL-33 with 180 Berger target hybrid. Barrel is a SS 29 1/4" 6 groove lilja.
Most accurate load is 83 grains for velocity of 3175 fps. I did work up to over 85 grains with velocities over 3200 fps but groups opened up.


I am certain RL-33 would work with the heavier 7mm bullet offerings in a 7mm/300 win mag.